Socket head screw



Jan. 16, 1951 G. H. J. BAULE 2,538,350

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Patented Jan. 16, 1951 UNITED STATES PATENT OFFICE Gerhard H. J. Baule,Salina, N. Y. I

Application September 5, 1945, Serial N0. 614,458

3 Claims. (01. 85 -45) This invention relates to threaded membersorscrews of various types, and has for its object a:

screw particularly for mass production or for assembly work by automaticmachines, although the screw is also operable by hand screw drivers,which screw is provided with a driving-tool-receiving recess or socketfor receiving the tool of such shape or formation that when the tool isreceived in the socket or recess, the screw because of the shape of therecess, is held from falling off while being transferred from thereceiving or pick-up station, magazine or hopper to the place the screwi to be applied and the tool releases from the screw by a withdrawingmovement of the tool. More specifically, it has for its object a screw,the head of which is formed with a noncircular or angular driving toolreceiving socket, at least a portion of which is twisted slightly or ofspiral formation of less than one convolution,

the spiral preferably leading in such direction that the tool leads intothe socket during 'turning in a driving direction and pulls out as thetool frees itself of the screw by withdrawing the tool with no turningforce applied. 7

The invention consists in the novel features and in the combinations andconstructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanyingdrawings in which like character designate corresponding parts in 2.1the views.

Figure 1 is an enlarged isometric view of a screw embodyingthisinvention.

Figure 2 is a plan view of parts seenin Figure 1.

Figure 3 is a fragmentary isometric sectional ew through the head of thescrew and contiguous portions of the shank.

Figure 4 is a view similar to Figure 3 of a slightly modified form.

Figure-5 is a view similar to Figure 4 of a second modified form.

Figure 6 is a sectional view of the screw head and one form of drivingtool for the screw.

l and 2 designate respectively the inner and outer recesses of adriving-tool-receiving socket, the socket being formed axially inthe'head 3 of a screw 4, the inner recess I only being twisted or ofhelical formation of less than one convolution, the helical curve beingclearly shown by the corners 5 formed by the side walls of the innerrecess 1. The socket, as here shown, is hexagonal.

The outer recess Zis here shown as, and preferably is, of largerdiameter than the inner rehere shown asa right angle.

cess l, but as indicated by its corner lines 6 of its polygonal sides ishere shown as not of helical formation, but it may be helical ofdifferent angle.

In the. form shown in Figures 1, 2 and 3, the wall of the outer recess 2is beveled or tapers from the outer face of the screw to the upper endof the inner recess 1. '-As shown in Figure 4, the outer recess 2:0 isformed with a circumferential wall 1 and a bottom wall 8 which meet atan angle,

The difference between the'operation of the recesses 2 and 20 will behereinafter set forth. In Figure 5, the spiral formation of the innerrecess is provided by spirally extending splines 8. The sockets may beformed byany suitable process and the socket here shown has a fiatbottom, although if formed with a boring tool would incidentally have aconical bottom.

The socket in the head of the screw is for receiving a screw-drivingtool of any suitable construction, and the outer recess coacts with thedriving tool to hold the screw from dropping off.

the tool afterit'has been picked up by the tool and is beingjransferredto the hole in which it is to be screwed. The 'tool itself may be of anyconstruction, and in Figure 6, l0 "designates the shank of aitool, whichis actuated inany suitable manner, the shank having a head, ll of spiralformation for turning into the socket or recess l thereof. Ajn axialmovable locking member, .as the sleeve I2, is slidably mounted on theshank H) of the tool, this sleeve being shown as beveled at its lowerend for entering the recess 2. This also is hexagonal, or the sameshape. in cross section as the recess 2'. The carrier l4 is here shownas guided in'grooves in a collar l-s1ecured to the shank ll) of thetool. The locking sleeve I2 is shown as pressed into locking position bythe spring l3 encircling the shank I0 and interposed between the collarl5 and the sleeve l2. As the tool enters the socket, the sleeve I2 ispushed back until the angles or corners of the sleeve aline with thecorners of the outer recess. When the spiral end of the tool enters theinner recess to some extent, the end of the sleeve will contact therecess 2, but at this time, the non-circular shape of the sleeve end isnot lined up with the noncircular shape of the recess. Continuing theinsertion of the spiral end of the tool by combined reaches a positionnear the bottom of the helical recess, the end of the sleeve I2 will bealined with and fit into the recess 2 and will hold the screw fromdropping by turning oil? the driving tool, the sleeve still beingyieldingly pressed into position by the spring 13. The locking sleevemay be Withdrawn against the action of the spring 13 by withdrawing thecarrier M for the sleeve. This carrier may be actuated in any suitablemanner. In the form shown in Figure 3, the tapered bottom of the outerrecess 2 serves as a cam to dislodge the sleeve l2 and overcome thelocking action when sufiicient withdrawing force entrance of the formerrecess and formed with is applied to the driving tool l0. Such pulling,

will tend to turn the tool, and hence the sleeve, in, a retrogradedirection. In the form shown 'in' Figure 4, the driving tool Hlispositively held from retrograde turning, when a withdrawing force isapplied, because the locking sleeve 12 fits" the angular channel orrabbet or recess 20 formed by its circumferential and'bottom" walls Iand 8. Hence in the form shown in liigure 4, it is necessary tomechanically and forcibly withdraw the locking member or sleeve 12before the driving tool can be pulled from thescrew or before the spiralhead of the driving tool-can be withdrawn from the spiralrecess l ofthescrew.

The method of forming thescrew with the driving recess forms no partOf'thiS'iHVBIltiOH.

In operation, the screw locks itself on the tool, due to the spiraltool-receiving recess I and the locking recess 2,

I What I claim is: 1. A screw having an axial, driving-tool-fittingsocket for a tool of complemental' contour, the socket including anon-circular inner recess of helical formation in which the helices atthe corners formed by the helices extend in a general directionlengthwise of the axis of the socket and the screw substantiallythe'depth of the recess, 4

and in which each is less than one convolution, and an outer recessinthe form of a countersink corner lines in line with the corner linesof the helicesi 1 15 3. A screw having an axial, polygonal, drivingtoolfitti'ng'socket for a tool of complemental contour',-the socketincluding an inner recess, the sides of which extend in a generaldirection parallel to the axis of the, screw, the corner lines of thepolygonal formation being helical and less than'one convolution, and anouter tool lock receiving recess in the form of a countersink at theentrance of the former recess, the outer recess being formed with cornerlines in line with the outer ends of the helices, the bottom of thecountersunk recess being beveled.

" GERHARD H. J. BAULE.

REFERENCES orrnn v The following references are of record in the file ofthis patent: I

' UNITED STATES PATENTS

